Yesterday, I went out to JFK Airport with no flight to catch and no visitors to greet. It was the annual Open House New York event, where private buildings and homes all over the city open to the public for a few hours, and it was a last chance to see the iconic TWA Flight Center before it is turned into a hotel. (You can see our photos from last year here.)

Native New Yorkers, retired flight attendants, tourists and architecture enthusiasts flooded the airy terminal, closed since TWA ceased operations in 2001, taking photos and sharing stories about the good old days of air travel. The mid-20th century was the high point in airport design; its airy and futuristic buildings can be appreciated by any modern day traveler who has ever had a layover at La Guardia.

We looked at some of the most iconic airport architecture in the U.S. and their current status. Is your favorite still flying?

%Slideshow-100872%DCA Terminal A – Washington D.C.’s first airport opened in 1941, and was considered to be the most modern in airport design at the time. In addition to its status as historic landmark and aviation icon, it’s also an archaeological site: the airport was built on a former colonial plantation and the birthplace of George Washington’s granddaughter.

Status: The original terminal was restored to its original look in 2004 and 2008, with the interior currently undergoing a massive renovation. You can still see many parts of the original lobby and building as it looked when President Roosevelt dedicated it. Check out some vintage postcards of the airport from the Boston Public Library.

IAD Main Terminal – One of Swedish architect Eero Saarinen’s airport designs, Dulles was designed in 1958 and dedicated in 1962, the same year the TWA terminal opened. The architect called the building and control tower “the best thing that I have done,” and inspired the design of Taiwan’s international airport. The “mobile lounges” were one of the most innovative concepts, carrying passengers in relative luxury from the terminal right to the plane

Status: Dulles wasn’t a popular airport from the beginning, as it didn’t allow jumbo jets until 1970 and the distance from the city is still off-putting, but it’s now one of the busiest in the country and is continuing to expand. The mobile lounges are still around, but the new Aero Train is more commonly used.

JFK Pan Am Worldport – The 1960 “flying saucer” was designed to bring the airplane to the passenger, sheltering the planes under the overhang for all-weather boarding. It was opened for Pan Am and renamed the Worldport in 1971 when it was expanded to accommodate the Boeing 747, and was the biggest passenger terminal in the world for several years. After Pan Am went bankrupt in the ’90s, Delta acquired the terminal and used it for many long-haul flights.

Status: Although it is on the list of the most endangered historic buildings and beloved by many airline and architecture enthusiasts, it looks like the Worldport is permanently grounded. While Delta just completed a major renovation of their other terminal at JFK, they need the room for airplane parking, and the flying saucer is already beginning to be demolished.

LAX Theme building – The distinctive Theme building is a perfect example of 1960s futuristic architecture, resembling something out of the Jetsons and actually inspiring the cartoon’s design. Part of the original ambitious plans for the airport was to connect terminal buildings with a giant glass dome, with the Theme Building serving as the main terminal, as in the picture above. One of the most famous buildings in the world, it’s photographed more than the Eiffel Tower.

Status: The Theme building has been a restaurant since 1997, and you can visit Encounter for a meal even if you aren’t flying. The free observation deck is open on weekends only if you just want to watch the planes taking off.

LGA Marine Air Terminal – For a passenger who arrives at one of La Guardia’s many dim and low-ceilinged gates, it’s hard to imagine that an Art Deco beauty is part of the same airport. Opened in 1940 and funded by the post-depression Works Progress Administration, the Marine Air Terminal originally served the glamorous Clipper planes, carrying 72 passengers on long transoceanic flights with sleeping berths and a high-end restaurant. The second World War made such flying boats obsolete, and the terminal sat unused for several decades.

Status: It’s now the main hub for Delta’s shuttle service to Boston, Chicago and Washington, even after a massive renovation to Delta’s other terminal at LGA. While it might have less modern facilities, it’s the only terminal to feature an original mural dedicated to flight (with a secret message).

LGB Main Terminal – The first trans-continental flight landed at Long Beach in 1911, but the Streamline Moderne terminal wasn’t built for another 30 years. The modernist building was considered avant garde at the time, but now feels classic and a bit romantic among airports, the kind of place you can imagine passengers boarding with hat boxes and cat eye sunglasses. Much smaller than nearby LAX, JetBlue made it a west coast hub in 2001 and put the California airport back on the map.

Status: Last year, LGB was fully modernized to make it more green and “resort-like,” with outdoor spaces outfitted with fire pits and cabanas. The renovation uncovered more of the mosaic tile art by WPA artist Grace Clements, then 28 years old, and covered by carpet for 70 years.